Functional trait effects on ecosystem stability: assembling the jigsaw puzzle

Under global change, how biological diversity and ecosystem services are maintained in time is a fundamental question. Ecologists have long argued about multiple mechanisms by which local biodiversity might control the temporal stability of ecosystem properties. Accumulating theories and empirical evidence suggest that, together with different population and community parameters, these mechanisms largely operate through differences in functional traits among organisms. We review potential trait-stability mechanisms together with underlying tests and associated metrics. We identify various trait-based components, each accounting for different stability mechanisms, that contribute to buffering, or propagating, the effect of environmental fluctuations on ecosystem functioning. This comprehensive picture, obtained by combining different puzzle pieces of trait-stability effects, will guide future empirical and modeling investigations.This study is the result of an international workshop financed by the Valencian government in Spain (Generalitat Valenciana, reference AORG/2018/) and was supported by Spanish Plan Nacional de I+D+i (project PGC2018-099027-B-I00). E.V. was supported by the 2017 program for attracting and retaining talent of Comunidad de Madrid (no. 2017-T2/ AMB-5406)

Synthesis, biological evaluation, and molecular modeling of nitrile-containing compounds : exploring multiple activities as anti-Alzheimer agents

Funding: EC COST Actions D34 and CM1103 for Short-term Scientific Mission funding (EM, DS, MM); the School of Biology at the University of St. Andrews (EJS, RRR); the Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa (AN, ACJ, TR, MCC); FCT, the Portuguese Foundation for Science and Technology (Project PTDC/SAU-NEU/64151/2006 (MCC), and project grant (DS) Vega 2/0127/18 and the contract No. APVV-15-0455 of Slovak Research and Development Agency (MM).Based on the monoamine oxidase (MAO) inhibition properties of aminoheterocycles with a carbonitrile group we have carried out a systematic exploration to discover new classes of carbonitriles endowed with dual MAO and AChE inhibitory activities, and Aβ anti‐aggregating properties. Eighty‐three nitrile‐containing compounds, 13 of which are new, were synthesized and evaluated. in vitro screening revealed that 31 , a new compound, presented the best lead for trifunctional inhibition against MAO A (0.34 μM), MAO B (0.26 μM), and AChE (52 μM), while 32 exhibited a lead for selective MAO A (0.12 μM) inhibition coupled to AChE (48 μM) inhibition. Computational analysis revealed that the malononitrile group can find an advantageous position with the aromatic cleft and FAD of MAO A or MAO B. However, the total binding energy can be handicapped by an internal penalty caused by twisting of the ligand molecule and subsequent disruption of the conjugation ( 32 in MAO B compared to the conjugated 31 ). Conjugation is also important for AChE as well as the hydrophilic character of malononitrile that allows this group to be in close contact with the aqueous environment as seen for 83 . Although the effect of 31 and 32 against Aβ1–42, was very weak, the effect of 63 and 65 , and of the new compound 75 , indicated that these compounds were able to disaggregate Aβ1–42 fibrils. The most effective was 63 , a (phenylhydrazinylidene)propanedinitrile derivative that also inhibited MAO A (1.65 μM), making it a potential lead for Alzheimer's disease application.PostprintPeer reviewe

Weak coordination between leaf drought tolerance and proxy traits in herbaceous plants

© 2021 The Authors.Increased drought is predicted to have a major impact on plant performance under environmental change. Yet leaf hydraulic traits directly related to drought tolerance, such as leaf turgor loss point (π), are under-represented in trait-based studies and have been largely overlooked within the main frameworks evaluating trait–trait coordination and trade-offs—the leaf economics spectrum (LES) and the global spectrum of plant form and function. Using 122 herbaceous species from the Central European temperate grasslands, we investigated (a) the coordination between π and traits often used as proxies for drought tolerance, namely SLA, leaf area (LA), leaf dry matter content (LDMC), leaf thickness (LT), plant height and intrinsic water use efficiency (iWUE); (b) whether the strength of the trait–trait relationships differed across plant functional types (PFTs: graminoids and forbs) and depended on species phylogeny; and (c) whether single or multiple traits, combined with either PFTs or phylogenetic relatedness, provide a good prediction of π. A more negative π (higher leaf drought tolerance) was coordinated with higher LDMC and higher iWUE. This pattern was consistent among PFTs and also after accounting for phylogenetic relatedness. However, the coordination of π with other traits was weak. For LT and height, it was driven by the differences between PFTs. For SLA and LA, it was only observed after accounting for phylogenetic relatedness. The most parsimonious model predicting π as a function of other traits retained LDMC and LA (adj. R = 0.37). Since π showed a strong phylogenetic signal, accounting for the influence of phylogenetic relatedness further improved π prediction by 17%. In herbaceous temperate plants, there is relatively weak coordination between leaf drought tolerance (π) and traits representing key dimensions of the LES and the global spectrum of plant form and function. None of the proxy traits considered here, alone or in combination, provided a strong prediction of π across a large number of grassland plant species. Therefore, our work emphasizes the need for direct measurements of leaf hydraulics when estimating plant drought responses to better understand and predict species responses to environmental change. A free Plain Language Summary can be found within the Supporting Information of this article.This study was supported by the project GAČR 20-08900S funded by Czech Science Foundation, the project RVO 67985939 funded by the Czech Academy of Sciences and the projects VEGA 2/0096/19 and 2/0147/21 funded by the Slovak Science Foundation. A.J.A. was funded by the Hungarian Eötvös Scholarship, J.D. and P.L. were supported by the MSMT INTER-EXCELLENCE project (LTAUSA18007) and F.d.B. was supported by the Plan Nacional de I + D + i (project PGC2018-099027-B-I00). The authors thank Adam Martin, Kevin Mueller and an anonymous reviewer for helpful comments on the previous versions of the manuscript. Open Access funding enabled and organized by Projekt DEAL. WOA Institution: Eberhard Karls Universitat Tubingen, Blended DEAL: Projekt DEAL

Weak coordination between leaf drought tolerance and proxy traits in herbaceous plants

© 2021 The Authors.Increased drought is predicted to have a major impact on plant performance under environmental change. Yet leaf hydraulic traits directly related to drought tolerance, such as leaf turgor loss point (π), are under-represented in trait-based studies and have been largely overlooked within the main frameworks evaluating trait–trait coordination and trade-offs—the leaf economics spectrum (LES) and the global spectrum of plant form and function. Using 122 herbaceous species from the Central European temperate grasslands, we investigated (a) the coordination between π and traits often used as proxies for drought tolerance, namely SLA, leaf area (LA), leaf dry matter content (LDMC), leaf thickness (LT), plant height and intrinsic water use efficiency (iWUE); (b) whether the strength of the trait–trait relationships differed across plant functional types (PFTs: graminoids and forbs) and depended on species phylogeny; and (c) whether single or multiple traits, combined with either PFTs or phylogenetic relatedness, provide a good prediction of π. A more negative π (higher leaf drought tolerance) was coordinated with higher LDMC and higher iWUE. This pattern was consistent among PFTs and also after accounting for phylogenetic relatedness. However, the coordination of π with other traits was weak. For LT and height, it was driven by the differences between PFTs. For SLA and LA, it was only observed after accounting for phylogenetic relatedness. The most parsimonious model predicting π as a function of other traits retained LDMC and LA (adj. R = 0.37). Since π showed a strong phylogenetic signal, accounting for the influence of phylogenetic relatedness further improved π prediction by 17%. In herbaceous temperate plants, there is relatively weak coordination between leaf drought tolerance (π) and traits representing key dimensions of the LES and the global spectrum of plant form and function. None of the proxy traits considered here, alone or in combination, provided a strong prediction of π across a large number of grassland plant species. Therefore, our work emphasizes the need for direct measurements of leaf hydraulics when estimating plant drought responses to better understand and predict species responses to environmental change. A free Plain Language Summary can be found within the Supporting Information of this article.This study was supported by the project GAČR 20-08900S funded by Czech Science Foundation, the project RVO 67985939 funded by the Czech Academy of Sciences and the projects VEGA 2/0096/19 and 2/0147/21 funded by the Slovak Science Foundation. A.J.A. was funded by the Hungarian Eötvös Scholarship, J.D. and P.L. were supported by the MSMT INTER-EXCELLENCE project (LTAUSA18007) and F.d.B. was supported by the Plan Nacional de I + D + i (project PGC2018-099027-B-I00). The authors thank Adam Martin, Kevin Mueller and an anonymous reviewer for helpful comments on the previous versions of the manuscript. Open Access funding enabled and organized by Projekt DEAL. WOA Institution: Eberhard Karls Universitat Tubingen, Blended DEAL: Projekt DEAL

A novel method to predict dark diversity using unconstrained ordination analysis

[Questions] Species pools are the product of complex ecological and evolutionary mechanisms, operating over a range of spatial scales. Here, we focus on species absent from local sites but with the potential to establish within communities — known as dark diversity. Methods for estimating dark diversity are still being developed and need to be compared, as well as tested for the type, and amount, of reference data needed to calibrate these methods. [Location] South Bohemia (48°58′ N, 14°28′ E) and Železné Hory (49°52′ N, 15°34′ E), Czech Republic. [Method] We compared a widely accepted algorithm to estimate species pools (Beals smoothing index, based on species co-occurrence) against a novel method based on an unconstrained ordination (UNO). Following previous work, we used spatially nested sampling for target plots, with the dark diversity estimates computed from smaller plots validated against additional species present in larger plots, and a reference dataset (Czech National Phytosociological Database of >30,000 plots as global reference data). We determined which method provides the best estimate of dark diversity with an index termed the “Success Rate Index”. [Results] When using the whole reference dataset (national scale), both UNO and Beals provided comparable predictions of dark diversity that were better than null expectations based on species frequency. However, when predicting from regionally restricted spatial scales, UNO performed significantly better than Beals. UNO also tended to detect less common species better than Beals. The success rate of combining UNO and Beals slightly outperformed the results obtained from the single methods, but only with the largest reference dataset. [Conclusions] The UNO method provides a consistently reliable estimate of dark diversity, particularly when the reference dataset is size-limited. For future calculations, we urge caution regarding the choice of dark diversity methods with respect to the reference data available, and how different methods handle species of high, and low, occurrence frequency.Grant Agency of the Czech Republic grant (GA16‐15012S; to Francesco de Bello and Lars Götzenberger). Long‐term research development grant from the Czech Academy of Sciences (RVO 67985939; FdB and LG). Czech Science Foundation ‐ Centre of Excellence PLADIAS (14‐36079G; Petr Šmilauer and Jan Lepš)

Synthesis, biological evaluation, and molecular modeling of nitrile-containing compounds: Exploring multiple activities as anti-Alzheimer agents

Based on the monoamine oxidase (MAO) inhibition properties of aminoheterocycles with a carbonitrile group we have carried out a systematic exploration to discover new classes of carbonitriles endowed with dual MAO and AChE inhibitory activities, and Aβ anti-aggregating properties. Eighty-three nitrile-containing compounds, 13 of which are new, were synthesized and evaluated. in vitro screening revealed that 31, a new compound, presented the best lead for trifunctional inhibition against MAO A (0.34 μM), MAO B (0.26 μM), and AChE (52 μM), while 32 exhibited a lead for selective MAO A (0.12 μM) inhibition coupled to AChE (48 μM) inhibition. Computational analysis revealed that the malononitrile group can find an advantageous position with the aromatic cleft and FAD of MAO A or MAO B. However, the total binding energy can be handicapped by an internal penalty caused by twisting of the ligand molecule and subsequent disruption of the conjugation (32 in MAO B compared to the conjugated 31). Conjugation is also important for AChE as well as the hydrophilic character of malononitrile that allows this group to be in close contact with the aqueous environment as seen for 83. Although the effect of 31 and 32 against Aβ, was very weak, the effect of 63 and 65, and of the new compound 75, indicated that these compounds were able to disaggregate Aβ fibrils. The most effective was 63, a (phenylhydrazinylidene)propanedinitrile derivative that also inhibited MAO A (1.65 μM), making it a potential lead for Alzheimer's disease application.European Cooperation in Science and Technology, Grant/Award Numbers: STSM CM1103-29512, STSM D34-05989, STSMCM1103- 29510; Portuguese Foundation for Science and Technology, Grant/Award Number: FCT -Project PTDC/SAUNEU/ 64151/2006 (MCC); Slovak Research and Development Agency (MM); Slovak Research and Development Agency; Foundation for Science and TechnologyPeer Reviewe